About

Johan Chu is the Sarofim Family Career Development Assistant Professor and an Assistant Professor of System Dynamics at the MIT Sloan School of Management. His research examines power, with a focus on how recently-developed technologies, including generative AI, enable low-cost, wide-reach communication and democratize access to global markets, knowledge, capital, and labor. He explores how these technological developments influence the dynamics of social contention and market competition, studying the factors leading to the durable dominance of nations, companies, products, ideas, and people. Additionally, Johan investigates how individuals and companies direct mass attention, a key source of power in a globalized age of abundant choice. His empirical work employs simulation, large datasets, social network analysis, machine learning, and computational text analysis, grounded in in-depth interviews and fieldwork with industry participants. His study contexts range from the effects of generative AI on the Korean film industry to K-pop star success, NBA competition, and market competition in the U.S. beer and mutual funds sectors, as well as societal power structures.

Research topics

• Medicine
• Engineering
• Intensive care medicine
• Medical emergency
• Economic growth
• Waste management
• Pharmacology
• Operations management
• Nanotechnology
• Internal medicine

Selected publications

• Abstract 1847: Closed-loop drug delivery system to personalize chemotherapy dosing

  Cancer Research · 2025-04-21

  article

  While most oncologists know that many chemotherapies are dosed on a body surface area (BSA) basis, fewer know that the equations used to estimate BSA are based on a study done over 100 years ago using data from just 9 people. Moreover, two patients with the same BSA can have many factors, such as body composition and genetics, which can impact a drug’s pharmacokinetics and pharmacodynamics, resulting in worse therapeutic outcomes. To solve this problem, we developed a medical device that can personalize the dose of chemotherapy to the patient during an infusion center visit. Our medical device, which we call CLAUDIA (the Closed-Loop AUtomated Drug Infusion regulator) is a closed-loop drug delivery system that measures the concentration of drug and changes the infusion rate in real time to keep the concentration of drug within the therapeutic window. CLAUDIA uses high performance liquid chromatography-mass spectrometry (HPLC-MS) as the sensor, which allows it to be relatively easily translated to control many different drugs, either individually or in a combination chemotherapy regimen. We demonstrate CLAUDIA can control the concentration of 5-fluorouracil (5-FU) in rabbits, which were manipulated to capture the pharmacokinetic variability observed clinically. We then adapted CLAUDIA to also control the concentration of irinotecan, demonstrating its ability to be rapidly translated to additional chemotherapies. Finally, we perform a cost-effectiveness analysis that demonstrates that CLAUDIA is cost-effective compared to the current standard of care for drug dosing of 5-FU (i.e., BSA). Overall, CLAUDIA presents promising medical device that can personalize the dosing of chemotherapy, which may be able to improve the therapeutic outcomes for multiple chemotherapies. Citation Format: Louis DeRidder, Kyle Hare, Ted Smierciak, Mia Chao, Aaron Lopes, Josh Jenkins, Nina Fitzgerald, Emmeline MacPherson, Niora Fabian, Josh Morimoto, Jacqueline Chu, Ameya Kirtane, Wiam Madani, Keiko Ishida, Johannes Kuosmanen, Naomi Zecharias, Christopher Colangelo, Hen-Wei Huang, Makaya Chilekwa, Nikhil Lal, Shriya Srinivasan, Alison Hayward, Brian Wolpin, David Trumper, Troy Quast, Douglas Rubinson, Robert Langer, Giovanni Traverso. Closed-loop drug delivery system to personalize chemotherapy dosing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 1847.

  PublisherDOI

• Closed-loop automated drug infusion regulator: A clinically translatable, closed-loop drug delivery system for personalized drug dosing

  Med · 2024-04-24 · 14 citations

  article
  PublisherDOI

• Antiretroviral Therapy Use and Disparities Among Medicare Beneficiaries with HIV

  Journal of General Internal Medicine · 2024-06-12 · 4 citations

  articleOpen access
  PublisherOA PDFDOI

• Surgery accelerates metastatic recurrence of PDAC: A novel, surgical, immune-competent mouse model

  HPB · 2023-01-01

  articleOpen access
  PublisherOA PDFDOI

• Coronary Microcirculatory Dysfunction in People With HIV and Its Association With Antiretroviral Therapy

  Journal of the American Heart Association · 2023-11-10 · 9 citations

  articleOpen access

  Background HIV infection and abacavir‐containing antiretroviral regimens are associated with vascular endothelial dysfunction and increased cardiovascular risk. Positron emission tomography (PET)‐derived myocardial blood flow reserve (MBFR), the ratio of vasodilator stress to rest myocardial blood flow, is a well‐validated measure of coronary microvascular health and marker of cardiovascular risk. Our objective was to compare MBFR among people with HIV (PWH) with matched non‐HIV controls and to assess whether switching from dolutegravir/lamivudine/abacavir to the non‐abacavir regimen bictegravir/emtricitabine/tenofovir alafenamide (TAF) would improve MBFR. Methods and Results Thirty‐seven PWH were 1:2 matched on cardiovascular risk factors to 75 people without HIV, and MBFR corrected for differences in resting hemodynamics was compared in a cross‐sectional design. PWH were majority men (68%) with a mean age of 56 years. Mean stress myocardial blood flow (1.83 mL/min per g [95% CI, 1.68–1.98] versus 2.40 mL/min per g [95% CI, 2.25–2.54]; P <0.001) and MBFR (2.18 [95% CI, 1.96–2.40] versus 2.68 [95% CI, 2.47–2.89]; P =0.002) was significantly lower in PWH than in people without HIV. In a single‐arm, multicenter trial, a subset of 25 PWH who were virologically suppressed on dolutegravir/lamivudine/abacavir underwent positron emission tomography myocardial perfusion imaging at baseline and after switching to bictegravir/emtricitabine/TAF. MBFR was unchanged after switching to bictegravir/emtricitabine/TAF for a mean of 27 weeks (MBFR, 2.34 to 2.29; P =0.61), except in PWH with impaired MBFR at baseline (<2.00; N=6) in whom MBFR increased from 1.58 to 2.02 ( P =0.02). Conclusions PWH had reduced coronary microvascular function compared with controls without HIV. Coronary microvascular function did not improve after switching from dolutegravir/lamivudine/abacavir to bictegravir/emtricitabine/TAF. Registration URL: https://www.clinicaltrials.gov ; unique identifier: NCT03656783.

  PublisherOA PDFDOI

• Improving the Consent Process With an Informed Consent Video Prior to Outpatient Colonoscopy

  Gastro Hep Advances · 2023-01-01

  articleOpen access

  <h3>Background and Aims</h3> Informed consent should allow patients the appropriate time and conditions to make decisions about their care. However, consent is often obtained immediately prior to a colonoscopy. We conducted a quality improvement study to assess how a preprocedure consent video 2 days prior to an outpatient colonoscopy impacts patient satisfaction. <h3>Methods</h3> Patients undergoing outpatient colonoscopy at a large academic medical center opted in to a text messaging platform for procedural information. Our intervention was an informed consent video 2 days before the colonoscopy. Our primary outcome was a composite patient satisfaction score. Pre and postintervention scores were compared using ordinal or multinomial logistic models to calculate odds ratios (OR) or relative risk ratios and 95% confidence intervals (CI), adjusting for age and sex. <h3>Results</h3> 1109 and 1452 patients completed ≥1 survey question in the pre and postintervention phases, respectively. Overall patient satisfaction did not differ between groups [OR for a 1-point increment in satisfaction score between post- vs preintervention groups = 1.05; 95% CI: 0.90–1.22; <i>P</i> = .51]. Compared to preintervention, postintervention respondents were more likely to report higher satisfaction with time available to talk with their physician (OR of a 1-point increase in individual question response = 1.29; 95% CI: 1.09–1.54; <i>P</i> = .004). Compared to preintervention, more physicians in the postintervention phase rated satisfaction with consent process efficiency as "very satisfied" or "satisfied" (<i>P</i> < .001). <h3>Conclusion</h3> An informed consent video prior to colonoscopy resulted in similar overall patient satisfaction. However, post-intervention, patients were more likely to report sufficient time to talk with their physician, and physicians reported higher satisfaction with consent efficiency.

  PublisherOA PDFDOI

• Modular Titratable Polypills for Personalized Medicine and Simplification of Complex Medication Regimens

  Advanced Healthcare Materials · 2023-08-01 · 13 citations

  articleOpen access

  Simplification of complex medication regimens in polypharmacy positively contributes to treatment adherence and cost-effective improved health outcomes. Even though fixed dose combination (FDC) drug products are the only currently available single dose poly-pill regimens, the lack of flexibility in dose adjustment of a single drug in the combination limits their efficacy. To fill the existing gap in drug dose personalization and simplification of complex medication regimens commonly encountered in the treatment of cardiovascular disease, tuberculosis, and tapering of corticosteroid therapy, a modular titratable polypill approach that simultaneously addresses both aspects is proposed. The polypill consists of modular units that contain different drugs at incremental or decremental doses to be assembled in a single titratable polypill at the required dose for each drug through a stacking or interlocking process. The variable dose (VD) modular tablets are subjected to quality control tests and found to comply to pharmacopeia's acceptance criteria and requirements specified in the respective drug monographs. A cost-effectiveness analysis is conducted supporting the VD strategy as cost-effective compared to the FDC strategy and more effective and less expensive than standard of care. The VD approach stands to enable pill burden reduction, ease of administration, enhancement of treatment adherence, and potential cost-saving benefits.

  PublisherOA PDFDOI

• S3150 When It Bleeds, It Pours: Esophageal Dieulafoy as a Rare Cause of Recurrent GI Bleeding

  The American Journal of Gastroenterology · 2023-10-01

  article1st authorCorresponding

  Introduction: Dieulafoy lesions are a well-known cause of recurrent overt obscure gastrointestinal bleeding. These cases can be frustrating due to the transient nature of the bleed and difficulty finding the source, resulting in frequent negative endoscopic evaluations. Though Dieulafoys are classically located in the proximal stomach, esophageal Dieulafoys have been rarely reported and may be the culprit lesion in some cases with otherwise “negative” upper endoscopies. Case Description/Methods: A 92 year old man with a history of coronary artery disease, aortic valve replacement, and chronic kidney disease presented to the hospital with large volume hematemesis. He had a similar presentation 1 week prior with hematemesis and melena. EGD performed at that time noted a hiatal hernia and erosions in the antrum, but was otherwise negative. He was discharged home on omeprazole. He then returned 1 week later with hematemesis with hypotension. Hemoglobin was 7. He was transfused and admitted to the ICU. A Dieulafoy lesion was suspected given the recent negative EGD. An emergent EGD was performed which found dark red blood in the esophagus and stomach. The proximal stomach was carefully lavaged and inspected, but did not reveal any source of bleeding. On withdrawal of the endoscope, a very small, slightly raised punctate red spot was seen in the distal esophagus. Upon probing, the lesion began bleeding briskly in a pulsatile manner, consistent with a Dieulafoy lesion. This was treated successfully with a 10Fr bipolar cautery probe with cessation of bleeding and destruction of the lesion. After several days of monitoring the patient was discharged home and has not had recurrent bleeding since. Discussion: Dieulafoy lesions require a high index of suspicion to diagnose given their subtle appearance. Negative upper endoscopies in patients with recurrent hematemesis are usually attributed to gastric Dieulafoys that cannot be seen due to their small size and rapid cessation of bleeding. However, atypically-located Dieulafoys, such as those in the esophagus, can be easily missed if not sought out. This case highlights the need for careful evaluation for small lesions throughout the GI tract that could represent a Dieulafoy, not only in the stomach, but also in the esophagus (1% of cases) and small bowel (15% of cases). If found, Dieulafoys can be successfully treated endoscopically in over 90% of patients with thermal or mechanical therapy.

  PublisherDOI

• Biodegradable ring-shaped implantable device for intravesical therapy of bladder disorders

  Biomaterials · 2022-08-17 · 13 citations

  articleOpen access
  PublisherOA PDFDOI

• Collaborative GI Fellow Project: Improving the Consent Process With an Informational Video Prior to Outpatient Colonoscopy

  Gastroenterology · 2022-09-19

  article
  PublisherDOI

Frequent coauthors

• Giovanni Traverso

  Brigham and Women's Hospital

  65 shared

• Adam Wentworth

  Mayo Clinic in Arizona

  48 shared

• Joy Collins

  Massachusetts Institute of Technology

  45 shared

• Peter R. Chai

  Harvard University

  41 shared

• James D. Byrne

  University of Iowa

  37 shared

• Chin Hur

  33 shared

• Hen‐Wei Huang

  Harvard University

  32 shared

• Alison Hayward

  27 shared

Labs

• System DynamicsPI

Education

• Resident physician

  Massachusetts General Hospital

• MD

  Stanford University School of Medicine

• BA

  Stanford University